This application is based on application(s) No. Hei 09-322954 and Hei 10-182109 filed in Japan, the contents of which are hereby incorporated by reference.
1. Field of the Invention
The present invention relates to an image-recording medium capable of being reused repeatedly wherein a printed material made to adhere to the image-recording medium by image formation in a copying machine, a printer, or the like is removable from the image-recording medium. More particularly, the present invention relates to an image-recording medium suitable for being applied to a removing means by physical frictional forces, such as a brushing method that uses an aqueous solvent, and also relates to a method of manufacturing such an image-recording medium and a method for removing the printed material from the image-recording medium by physical frictional forces such as brushing.
2. Description of the Related Art
Electrophotographic copying techniques using toners (so called copy simply) are popular now. Image-recording media such as paper and OHP sheets are used in large quantities.
Printed materials printed or copied on such image-recording media are not easily removed. Techniques for removing such printed materials are not yet ready for practical use. It is true that printed materials generated in large quantities in offices are discarded when they become unnecessary.
This is clearly not desirable from the point of view of environmental protection and natural resource preservation. Therefore, researches on techniques for reproducing or recycling image-recording media which would otherwise be discarded have been vigorously conducted. Japanese Patent Laid-Open No. Hei 7-311,523 and EP060152, for example, disclose methods wherein a swelling layer which swells by absorbing water is formed on the surface of an image-recording medium and images printed on the image-recording medium are removed by swelling the swelling layer with water.
In reality, however, the conventional methods have not been put into practical use, because of their inability to sufficiently and satisfactorily remove printed materials and because of problems involving the durability of the image-recording medium.
In particular, the surface layer changes its volume by absorbing water while the volume of the base layer remains unchanged, and also the surface layer is subjected to a stress by physical force applied to remove the printed material on the swollen surface layer. Because of these reasons etc., the surface layer tends to be peeled off. It is an important technical subject to fix the water-swelling surface layer on the base layer.
An object of the present invention is to provide a novel and useful recyclable image-recording medium that allows printed materials such as toners adhering thereto to be removed.
It is also an object of the present invention to provide a recyclable image-recording medium having excellent durability.
A further object of the present invention is to provide a method of manufacturing such an image-recording medium and a printed material-removing method that uses such an image-recording medium.
The present invention provides a recyclable image-recording medium comprising a base layer, an intermediate layer and a water-swelling surface layer; a manufacturing method of the recyclable image-recording medium; and a printed material-removing method that uses such an image-recording medium.